P320. The presence of fistulae at baseline does not increase the incidence of adverse events in patients with Crohn's disease in the infliximab ENCORE registry
G. D'Haens1, W. Reinisch2, J.-F. Colombel3, J. Panes4, S. Ghosh5, C. Prantera6, S. Lindgren7, D.W. Hommes8, Z. Huang9, S. Huyck10, D.K. Chitkara11, 1Academic Medical Center, Inflammatory Bowel Disease Centre, Amsterdam, Netherlands, 2Medical University, Department of Internal Medicine III, Vienna, Austria, 3Icahn School of Medicine at Mount Sinai, Department of Gastroenterology, New York, United States, 4Hospital Clinic I Provincial, Department of Inflammatory Disease, Barcelona, Spain, 5University of Calgary, Department of Medicine, Calgary, Canada, 6AO San Camillo Forlianini, Gastroenterology Operative Unit, Rome, Italy, 7University Hospital MAS, Department of Gastroenterology, Malmö, Sweden, 8University of California Los Angeles, Center for Inflammatory Bowel Diseases, Los Angeles, United States, 9Merck Sharp & Dohme, Department of Epidemiology, Kenilworth, United States, 10Merck Sharp & Dohme, Department of Statistics, Merck Research Laboratories, Kenilworth, United States, 11Merck Sharp & Dohme, Department of Clinical Research, Kenilworth, United States
Prospective registries are the best tools to collect long-term safety data on infliximab (IFX) for Crohn's disease (CD). This study evaluated the impact of the presence of fistulae at baseline on adverse events (AEs) in patients receiving treatment for CD as part of a 5-year registry.
The European National Crohn's Observational Registry (ENCORE; NCT00705614) is a prospective, observational safety surveillance registry of 3 patient groups with CD who received different therapies: standard nonbiologic therapy (STD), IFX therapy, or switched from STD to IFX (S2IFX). Enrollment from 9 EU countries occurred from 2003 to 2008; patients were to be followed for 5 years. AEs were analysed descriptively by treatment group and fistulae status (ie, draining fistulae present or absent in the 4 weeks prior to baseline).
2662 patients enrolled in ENCORE in the STD group (N = 1121), IFX group (N = 1541), and S2IFX group (N = 298). The median follow-up duration (min-max) was 55.6 months (0–73), 60.4 months (0–87), and 42.5 months (1–67) for the STD, IFX, and S2IFX groups, respectively. At baseline, the IFX and S2IFX groups had greater disease severity than the STD group. More patients in the IFX group had draining fistulae in the 4 weeks prior to baseline (23.9%) than in the STD group (9.4%) or S2IFX group (8.4%). In the STD and IFX groups, the overall incidence of AEs did not differ for patients with vs without baseline fistulae; in the S2IFX group, incidence was higher for patients without than with fistulae (Table). For serious AEs, the incidence for patients with vs without baseline fistulae varied across the 3 treatment groups; in the IFX group, incidence was similar with vs without baseline fistulae (50% vs 51.8%).
Serious infections were slightly greater in patients with vs without fistulae in both the combined IFX/S2IFX group (with fistula: 9.2%; without fistulae: 7.3%) and the STD group (with fistulae: 5.7%; without fistulae: 3.7%). Patients with fistulae were more likely than those without fistulae to have fistula-related infections, regardless of treatment group. The incidence of overall and serious fistulae-related infections did not increase consistently over 11 study visits in any of the treatment groups.
|Any AE, n (%)||Any serious AE, n (%)|
|Standard therapy with fistulae (N = 105)||69 (65.7)||42 (40.0)|
|Standard therapy without fistulae (N = 1015)||655 (64.5)||349 (34.4)|
|IFX with fistulae (N = 368)||306 (83.2)||184 (50.0)|
|IFX without fistulae (N = 1173)||994 (84.7)||608 (51.8)|
|Switched to IFX with fistulae (N = 25)||20 (80.0)||9 (36.0)|
|Switched to IFX without fistulae (N = 102)||94 (92.2)||65 (63.7)|
In the ENCORE registry, the presence of fistulae at baseline was not associated with an increased incidence of AEs or serious AEs in CD patients in the IFX group. This study was funded by Merck & Co.